How private are our activities on the Internet? According to Julia Angwin, not very. In her new book, Dragnet Nation, Angwin discusses the increasingly pervasive culture of surveillance and data-gathering online, as well as why Internet anonymity is a myth.

To learn more about Angwin's book, and to listen to her interview on NPR's Fresh Air, click here.

Angwin on the "illusion of anonymity" on the Internet:

"A lot of the online tracking was originally justified as being completely anonymous and so we shouldn't worry about it because our names weren't in those databases — it's just cookie number "123456" went to these websites. But there's been a lot of research that shows that basically people's traces and actions are very unique and when you get a large set of data that has all these varied specific actions taken by people, that you can re-identify them. ... What we're learning is that we can be re-identified and in fact, much of the tracking that's going on is becoming more identified — Facebook, Google, Twitter, they know who you are already, they know your name most likely, and they're tracking you across the Internet. So they also are blurring the line between the anonymous and the non-anonymous tracking."